Is this normal trying to balance Carbimazole?

[micadog]

I am now about 7 weeks in to my treatment for Graves. I think it has been a bit strange, but those of you with far more experience may be able to tell me differently! I started on 20mg of Carbimazole. After 3 weeks my T3 and T4 were in their normal levels but a very low TSH. We reduced me down to 15mg for three weeks. After two weeks I rang my endo to say my heart rate was quite lowered so we did more bloods. TSH back to normal but T4 down to 4. I also had a UTI. So I am taking antibiotics (Trimethoprin) and off the carbimazole for a week to go back on at 5mg per day. I have been feeling a bit headachy and dizzy but put it down to the antibiotics. However, my heart rate has increased today and I have a slight tremour. Is it possible to react to no carbimazole after just 3 days of not taking it?Would I be right in says I may have a problem finding the right dose for me as I might be a bit "sensitive" as my endo said. Any thoughts most appreciated!

[asiatic]

As you are only into your 7th week of treatment it is early days and it is not unusual to react quite quickly to Carbimazole and need titrated down as you become hypothyroid. It is good you are being monitored although I do not understand why ATM was stopped but am no expert and there may have been good reason. You are probably back to being hyper again. Normally treatment lasts 18 months at least to give your antibodies time to reduce. I see sawed between hyper and hypo too and managed better on block and replace which is an option you might want to discuss with your doctor. Carbimazole is given to block your thyroid and give it a rest. Levothyroxine is added in to replace the thyroid hormone you have stopped producing.

[micadog in reply to asiatic]

Interesting.. thank you very much!

[SlowDragon Administrator]

Recommend getting vitamin D, folate, ferritin and B12 levels tested

These need to be optimal for thyroid hormones

Common to be low with Graves’ disease

[PurpleNails Administrator]

What is difficult to manage with carbimazole is although it works very quickly - (within hours) it works by inhibiting the production of new hormone. This is achieved by stopping iodine being converted to a usable form for the thyroid to make new T4 & T3.

The body has to use any pre existing stores, and this is said to take up to 8 weeks, so you kind of have an ever adjusting picture. Especially If your dose is altered/stopped randomly or your Graves fluctuates wildly. tritiation method will not be able to keep up these changes, even with regular, repeat testing and dose adjustment.

Dose should always be adjusted by FT3 & 4 never the TSH as the TSH can take ages to respond, It can trail behind considerably, and sometimes never recovers. For example I have hyper from a toxic nodule, so at diagnosis my FT3 was almost double, FT4 borderline high and TSH totally suppressed. (This is considered mild, Graves can reach 3 or 4 times the normal range) Two years on my frees are low but In range but my TSH has never quite made it into range. It almost rose into range once but then dropped again.